Strong and highly variable push of ocean waves on Southern Ocean sea ice

Significance Southern Ocean sea ice plays a key role in regulating the uptake of carbon and heat by the global ocean. In this context, ocean waves have a strong influence, including ice break-up and pancake formation. These processes explain large differences in sea-ice properties between Arctic and Antarctic. Waves also decay in the ice, exerting a force in their propagation direction that compacts the ice. Here, we provide an extensive dataset on wave heights and its decay in sea ice, using satellite imagery. Wave decay can be much faster than previously reported but is highly variable. The resulting wave force on the ice can have a profound impact on both ice extent and thickness.